In mammals, the only endogenous pathway for choline biosynthesis is the methylation of phosphatidylethanolamine to phosphatidylcholine (PC) by phosphatidylethanolamine N-methyltransferase (PEMT) coupled to PC degradation. Complete choline deprivation in mice by feeding Pemt(-/-) mice a choline-deficient (CD) diet decreases hepatic PC by 50% and is lethal within 5 days. PC secretion into bile is...

The development of a FIA system for the determination of total choline content in several types of milk is described. The samples were submitted to hydrochloric acid digestion before injection into the system and passed through an enzymatic reactor containing choline oxidase immobilised on glass beads. This enzymatic reaction releases hydrogen peroxide which then reacts with a solution of iodid...

A method that overcomes the difficulties of the 240-nm benzoylcholine method for phenotyping plasma cholinesterases has been developed. After a timed reaction, under the same reaction conditions as in the classic procedure, choline is detected at 500 nm by use of choline oxidase coupled with the peroxidase/phenol/aminoantipyrine system. Cholinesterase activity measurements, calibrated by use of...

A multi-functional luminol-reduced Pt@Au hybrid flower-like nanocomposite (luminol-Pt@AuNF) which not only acts as an efficient signal probe but also constitutes a pseudobienzyme amplifying system with choline oxidase (ChOx) was firstly synthesized and applied to the construction of a solid-state luminol electrochemiluminescence (ECL) immunosensor for cardiac troponin I (cTnI) detection.

Real-time monitoring of betaine aldehyde metabolism at high temporal resolution was accomplished using a hyperpolarized choline analog and (13)C-NMR. This represents the first observation of an aldehyde intermediate on hyperpolarized MR and opens the way for kinetic studies of oxidase/dehydrogenase enzymes in vitro and in vivo.

A collaborative study was conducted on a coupled enzymatic-spectrophotometric method for the determination of choline in infant formula and milk powders. Twenty-nine laboratories participated in the analysis of 8 blind duplicates over the range of 45-175 micrograms/100 g sample. After the combined acid hydrolysis-phospholipase release of choline, incubation with choline oxidase in the presence ...

D-Arginine dehydrogenase (DADH) catalyzes the oxidation of D-arginine to imino arginine using FAD as the cofactor. The enzyme is part of a recently discovered two-enzyme complex from Pseudomonas aeruginosa involved in arginine utilization. Function of the enzyme within the organism is unknown. Work on this enzyme has been undertaken to understand the structure as well as its reaction mechanism ...

Conversion of ethanolamine to choline (l), with methionine serving as the methyl donor (2), has been established in the intact animal. Stetten (1) observed that the labeled nitrogen of ethanolamine-N15 was retained in the choline molecule, and we determined that the carbon chain of ethanolamine is the precursor in vivo of the choline carbon chain (3). Conversion of ethanolamine to choline by in...

In several recent publications (14) it has been reported that dietary aminopterin produces a marked decrease in rat liver choline oxidase activity as measured by the whole homogenate technique. A simple folic acid deficiency, however, has been shown to produce only slight changes in the activity of this enzyme (5). It was probable that a simple folic acid deficiency did not deplete the tissues ...

In a 42-d experiment, 576 one-day-old Vencobb 308 broiler chicks were used to investigate the effects of lecithin extract (0.5 g/kg), choline chloride 60% (1 g/kg) and Bio choline (1 g/kg) in diets of moderate and high energy in a 4 × 2 factorial arrangement on performance and certain physiological traits in broiler chickens. The inclusion of Bio choline and lecithin extract in the diet signifi...